Electric soldering apparatus



Sept. 18, 1945.

G. L WARD ELECTRIC SOLDERING AIPARA'I'US Filed June 10, 1945 1 L. Ill/-J 2 "a 2 Sheets-Sheet 1 Inventor 6401?: M1; 'Wmd,

Attorney G. L. WARD ELECTRIC SOLDERING APPARATUS ,s e us', 1945,

Filed June 1'o. 194:5 2 Sheets-Sheet 2 Inventor Gemye low: "@111. Z2 ByAttorney Patented Sept. 18, 1945 ELECTRIC SOLDERING APPARATUS GeorgeLouie Ward, Northwood, England, assignor to Standard Telephones andCables Limited, London, England, a British company Application June 10,1943, Serial No. 490,247

In Great Britain June 19, 1942 4 Claims. (Cl. 219-12) This inventionrelates to electric soldering apparatus. In my application Serial No.424,231, filed Dec. 24, 1941, I have described and claimed a form offoot operated soldering apparatus (thus leaving both hands free formanipulation of the soldering operation) which is adapted for use withany size of work or in any location.

It is the object of the present invention to provide a solderingapparatus which is somewhat more robust than the forms of apparatusdescribed in the above mentioned specification.

According to the present invention I provide electric solderingapparatus comprising an overhanging support adapted to be mounted on abench and an electric heater or an electrically heated bit fixed to aplunger moveable vertically in said support so as to be brought down andremoved from work to be soldered.

Preferably the electric heater or electrically heated bit is operated bymeans of a treadle, thus a leaving both hands free for manipulation ofthe soldering apparatus.

Preferably also the overhanging support is made of two mutuallyinsulated portions which construction allows of the apparatus beingadapted for use in several different ways, as will be clear from thefollowing description.

The nature of the invention will be better understood from the followingdescriptionof one embodiment thereof taken in conjunction with theaccompanying drawings in which:

Fig. 1 is a side view of the embodiment;

Fig. 2 is a plan view; and

Fig. 3 is a sectional view of the head of the apparatus.

Referring to the drawings, a curved arm 3 is supported on base plate Iwhich in turn is adapted to be fixed by screws 4 to a work bench 2. The

curved arm 3 resembles in shape that commonly used to support a drill orother similar vertically mounted machine tool, but is splitlongitudinally into two portions 3a and 3b insulated from one another.These portions are cast integrally with portions 5c and 5d respectivelyresting on the base plate I, and are made of electrically conductingmaterial. Terminals 6a and 6b for attachment of cable lugs are mountedexternally of the two portions 3a and 3b of the arm, and terminals 5aand 5b are mounted on the portions 50 and 5d. The terminals 6a and 6bare mounted on a bolt 8 on which is an insulating washer 1 separatingthe two portions 3a and 3b of the arm. An insulating bush 9 fits overthe bolt 8 to insulate the portion 3a of the arm from the bolt.

The flat base portions 50 and 5d of the arm portions 3a and 3b aresecured to the conducting base I, with the interposition of aninsulating plate I l.

The portion 3a of the arm 3 ends in a circular boss inside which fits abush l2 held therein by screws l3. Thisbush I2 is slotted for entranceof a Bowden cable M which passes from the underside of the bench 2 andin a slot in the inner side of the portion 3a of the arm. The outersheath of the Bowden cable I4 is secured in several places in the saidslot and to bush l2. A plunger I1 is a sliding fit inside the bush l2and a cap I8 is attached to the upper end of the plunger H. The innerwire of the Bowden cable I4 is secured by a nut I6 to the cap 18. Acoil-spring I9 is held between the cap I8 and the bush l2. A solderingtool (not'shown) can be held in the plunger I! by means of a screw (Fig.1). A covering 50 fits over the upper part of bush [2 and plunger I1 andrests on boss Ill.

The inner wire l5 of the Bowden cable passes through the bench 2 and issecured to a nipple 2| which screws into a connecting collar 22. A rod23 screws into the connecting collar 22 and passes into a barrel 24 andis held by a set screw e The extent to which the rod 23 is within thebarrel 24 is adjustable in accordance with the height of the bench 2above the ground.

A rod 26 passes into the barrel 24 and carries a collar 29 between whichand a cap 28 is a coil spring 30. The rod 26 is secured to a shackle 21secured in turn to a treadle 3|. The treadle 3| is pivoted at 34 andcarries an arm provided with a stop member 36. The stop member 36 isheld against a fixed stop 31 by a spring 33 attached to the treadle 3|and a base plate 32. The position of the stop 36 in the arm 35 isadjustable as is also the position of the fixed stop 31. The positionsof the stops 36 and 31 are adjustable in accordance with the height ofthe tool secured in plunger I! above the bench 2. An electric switch issecured to base plate 32 in such position that when the tool is broughtdown on to the work to be soldered stop member 36 just touches a switchplunger 39. A further depression of the treadle then compresses spring30 and causes stop 36 to actuate switch plunger 39 to close the switch.

The positions of switch 40 and the fixed stop 31 in relation to the stop36 may be reversed, the switch 40 being then arranged so that pressureon the plunger 39 opens the switch. In this case the switch 40 would beclosed soon after the movement of stop 36 with the treadle had commencedand a positive limitation to the extent to which terminals 4! and 43 areinsulated'frorn the base plate I whilst the middle one 42 iselectrically connected thereto. In the drawings the outer terminals 4|and 43 are shown connected by straps 44 and 45 to terminals 5b and 5aand in such case of course the external electric supply is connected toterminals 41 and 43. The terminals 6a and 5b are then connected by shortlengths of flexible cable to the terminals of an electrical heater forthesoldering tool.

The electrical heater may take the form of a split carbon cylinder thetwo halves of which are mounted in an insulating manner in plunger l1and adapted to be bridged by the work to be soldered (usually ofcircular form). When this split carbon cylinder is brought down on tothe work the'latter forms an electric connection between them and whenswitch) is closed the current flows, the carbon then serving as aheater.

Another .form of soldering tool which may be used is a plain carbon rod.When this is secured in plunger I! the electrical connections are suchthat the external supply is connected to the terminal 43 and to terminal42. As stated above terminal 42 is connected to base plate I. Strap 44is removed. The electriccircuit is then completed between the carbon rodand the work to be soldered.

Although the portionSa of the arm 3 is conducting and thusserves as anelectrical connection fromterminal 5a to the carbon rod'mounted inplunger H, the electrical connection between plunger Hand thebush I2'may not be a very good one and it is preferred also to connect ashortlength of flexible cable between the terminal 6a and the carbon rodmounted in plunger ll.

:Thetool mounted in plunger 11 may also .take the form of a copper bitheated by means of a wound form of. heater or by means of two carbonrods; .The terminals of the wound heater or of the-carbon rods areconnected by short lengths of flexible cable to terminals 6a and 6b.

. The base plate I is provided with a groove or grooves 45 in whichmaybe clampedholders for abody to be soldered.

The plunger I! may be used as a pressure medium upon or as a conductingbridge between two portions of a body mounted'insulatingly upon the baseI, the terminals 4| and 43 being then connected by flexible cables withthe respective portions.

What is claimed is:

1. An electric soldering apparatus comprising means for holding a workpiece, means for receiving at least one electric heating element, meansfor moving the receiving means with respect to the holding means toapproach and separate said heating element and said work piece, astructure supporting the receiving means, means for supplying electriccurrent to said heating element in two insulated electric paths formingpart of said structure, means for supplying current to a third electricpath including the holding means so as to connect selectively eithersaid two electric paths through said work piece, or one of said twoelectric paths through said work piece with the third electric path.

2. An electric soldering apparatus comprising means for holding a workpiece, means for receiving at least one electric heating element, meansfor moving said receiving means with respect to said holding means toapproach and separate said heating element and said work piece, astructure supporting the receiving means, and comprising two insulatedarms one of which carries-thereceiving means, means for supplying.electric current to said heating element through said arms, means forsupplying current to a'third electric path including said holding meansso as to connect selectively either said two electric paths throughsaidwork piece, or one of said two electric paths through said workpiece with the third electric path.

3. Anelectric soldering apparatus comprising a holder for a work pieceattached to a base plate, a plunger for receiving at least one electricheating element, means for moving said plunger with respect to. saidholder to approach and separate. said heating elemhnt. and said workpiece, a structure attached to' said base plate attached mechanicallyto, but insulated electrically. fromysaid base plate and supportingrsaidplunger; means for supplying electric current to said heating element intwo insulated electric paths forming part' of" said structure, means forsupplying current to a third electric path includingsaid base plate andsaid holder so as to connect selectively either said two electric pathsthrough :said work piece,. or, one of said two electric: paths throughsaid work piece with .Sflldsthlld electric path.

. 4. An electric soldering. apparatus comprising means .forho'lding awork piece, a plunger receiving at :least :onei'electric heatingvelement, means for movingsaid plungertwith respect to the holding meansto approach and separate said heating'elernent and-said work-piece, astructure supporting said plunger and comprising two insulated arms oneof which carries :said plunger, means for supplying electric current to.said heating elementthrough said arms, means for supplying current to athird electric path including said holding means so as to connectselectively either said two electric paths through said workpiece,.- orone of said two electric paths throughsaidwork piece with the thirdelectric path.

. GEORGE LOUIE WARD.

